Random-access robotic inventory dispensary: multi-pick fulfillment

ABSTRACT

The present invention is a robotic system for maintaining product inventory and dispensing products upon request from a customer or other user. Product items are stored in an inventory storage unit (ISU), one item per bin. Controller logic allows items to be stored in, and retrieved from, arbitrarily-assigned storage locations. The bins hang on rails within drawers. Upon a request from a consumer (or other user) for a plurality of product items, the robot retrieves a bin holding the first item from the ISU, and places the bin onto a shelf that moves with the robot. The additional items are handled similarly. Once all the items are on the shelf, the robot transfers them to a dispensing chute to the consumer.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is related to U.S. application Ser. No. ______, filedDATE, and entitled “Robotic Inventory Storage and Dispensary: VariableBin Height”. This application is related to U.S. application Ser. No.______, filed DATE, and entitled “Robotic Inventory Storage andDispensary: Replenishment and Purge”. Both these applications are herebyincorporated by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to a random-access robot-implementedinventory storage and dispensary system. Specifically, it relates tomulti-pick fulfillment in such a system.

BACKGROUND OF THE INVENTION

A “user interface” (UI) allows a user to interact with a computer orprocessing system. A UI may contain a display, tactile controls, orperipheral devices (e.g., mouse, touch pad, joystick) to facilitateentering data and making selections. The processing system, undercontrol of one or more computer processors, might provide a graphical UI(GUI) though the display. A GUI might or might not include touchcontrols.

A “database” stores and organizes data in any number of file structuresand tangible computer-accessible storage devices, in any format. A“database system” (and, indeed, a database) may be hierarchical, andinclude one or more databases, possibly of a variety of differentcontents, types, formats, and access means. For example, a database in adatabase system might be a relational database, an object-orienteddatabase, a flat text file, or a collection of images or audio/videotracks.

By “logic” we mean hardware, and software instructions executing on thathardware, that executes instructions, makes decisions, and initiatesactions.

A “robot” is an apparatus or system that performs physical tasks undercontrol of a processing system or controller, which executes controllerlogic. Note that two robots, each with separate controllers, may beunder common supervision or direction by a single controller. Thiscombination of robots may be regarded as a single robot. Similarly, ifrobot A directs robot B, the combination of A and B may be regarded asitself a robot. In some instances, to emphasize that two or more robotsmight be involved, we may use the term “robotic system” rather than“robot.”

A “scanning system” consists of one or more scanners acting under acommon control. Each scanner in the system has a respective scanningtechnology, scans specific types of objects, and obtains from thoseobjects specific types of information. Between any two scanners in thesystem, the technologies used may be the same or different; the types ofobjects may be the same or different; and the types of information maybe the same or different. A scanning system might or might not be partof a robotic system.

A “product item” is an individual instance of a product model. A“product type” is a set of product items having something in common. Thefollowing are exemplary product types: all product items of a givenmodel or stock-keeping unit (SKU); all product items from a givenmanufacturer; all product items from a given supplier; all product itemshaving a given functionality (e.g., video cameras); all product items ofa given model having a particular color; all product items of a givenvariety (e.g., freeze-dried strawberries) and shelf-life or sell-bydate; a set of individually-identified product items.

Herein, we will regard the terms “replenish” and “restock” as synonyms.

SUMMARY OF THE INVENTION

The present invention is a robotic inventory dispensary (RID); that is,a robotic system for maintaining product inventory and dispensingproducts upon request from an “RID-consumer” or “consumer.” In a retailenvironment, a consumer might be a customer, a staff member, anotherautomated system, or an operator of the RID. Product items are stored inan inventory storage unit (ISU), one item per bin. Controller logicallows product items to be stored in, and retrieved from,arbitrarily-assigned storage locations. Because contents of any storagelocation in the RID can be accessed by the robot directly at any time,the RID is random-access. Such access may include, for example, couplingto (e.g., magnetically) and removing any bin from the RID; removing aproduct item from a bin; inserting a bin into the RID; transferring abin from one location in the ISU to another; transferring a product itemfrom a bin from ISU to a dispensing apparatus (e.g., a dispensing chute,a conveyor, or an operator access drawer); transferring a bin from anoperator access device into the ISU; and compressing any storage areawithin the ISU where bins are stored.

The RID may include a set of prioritization modules in a storageprioritization scheme, and allow the currently-active module to bechanged to another modules, or parameters constraining thecurrently-active module to be set or modified through a UI or bycontroller logic. A prioritization scheme governs the relative priorityattached by the robot to sequence tasks it is required to perform.

Bins in the ISU hang on rails arranged as drawers. In a replenishmentoperation, the system transfers empty bins to an operator station forreplenishment. An “RID-operator” or “operator” fills the empty bins withproduct items. The system inserts these bins into drawers of the ISU. Ina purge operation, the operator enters an identifier of a product typeto be removed. The system moves the bins containing the affected itemsto the operator station. After the product items are removed, the emptybins are moved back into the ISU.

Some embodiments allow bins to have variable heights. Configuration ofthe rails may facilitate such bins of variable height. Vertical movementof the rails may be automated.

Some embodiments allow multiple product items to be picked from thestorage by the robot before any of them are dispensed. In suchembodiments, upon a request from a consumer for a plurality of productitems, the robot retrieves a bin holding the first item from the ISU,and places the bin onto a shelf or other temporary storage that moveswith the robot. The additional items are handled similarly. Once all therequested product items are in temporary storage, the robot transfersthem to a dispensing chute to the consumer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating categories of users of anexemplary robotic inventory dispensary (RID).

FIG. 2 is a block diagram illustrating functional and structuralcomponents of an exemplary RID.

FIG. 3a is a front view of an inventory storage unit (ISU) and a robotof an exemplary RID.

FIG. 3b is a Cartesian coordinate system that is helpful in describing aRID. The previous figure is viewed in the y direction.

FIG. 3c is a break-out showing the structure of an exemplary arm of arobot.

FIG. 3d is a stick diagram illustrating an alternative arrangement oftilt axes for an arm of a robot.

FIG. 4 is a conceptual diagram illustrating an exemplary storagehierarchy in an ISU.

FIG. 5a is an isometric view of an exemplary RID using a conveyor foroperator access.

FIG. 5b is an isometric view of an exemplary RID having an operatoraccess drawer.

FIG. 6 is a block diagram illustrating exemplary tasks that might beexecuted by a robot in a RID.

FIG. 7 is a block diagram illustrating exemplary functional andstructural components of a controller of a RID.

FIG. 8 is a block diagram illustrating exemplary tasks that might beexecuted by a controller of a RID.

FIG. 9 is a block diagram illustrating exemplary types of data thatmight be maintained and managed by a controller of a RID within adatabase system.

FIG. 10a is a side view of a first exemplary ISU bin that contains aproduct item.

FIG. 10b is a front cross-section at A-A through the ISU bin of theprevious figure.

FIG. 11a is a side view of a second exemplary ISU bin that contains aproduct item.

FIG. 11b is a front cross-section at B-B of the ISU bin of the previousfigure.

FIG. 12a is a front cross-sectional view through an exemplary column ofrails and bins in an exemplary ISU, the rails positioned to form drawersthat are variably-spaced in the vertical.

FIG. 12b is a front cross-sectional view through an exemplary column ofrails and bins in an exemplary ISU, the rails positioned to allowdrawers that are equally-spaced in the vertical.

FIG. 13a illustrates how equally-spaced rail mount points might be usedto implement variably-spaced racks in an exemplary ISU.

FIG. 13b illustrates how equally-spaced rails might be used tofacilitate bins of varying height.

FIG. 14a is a flowchart illustrating how exemplary logic in a RID,typically executed by a controller, might prioritize tasks of fulfillingpurchase requests; replenishment/purge tasks; and compression ofdrawers.

FIG. 14b is a state diagram illustrating an exemplary priority systemfor a RID.

FIG. 15 is a conceptual diagram illustrating how an exemplary RID mightfulfill a request from a consumer for one or more product items.

FIG. 16a is a conceptual diagram illustrating an exemplary RIDtransferring empty bins from an ISU to an operator station as part of areplenishment task.

FIG. 16b is a conceptual diagram illustrating an exemplary RIDtransferring filled bins from an operator station to an ISU as part of areplenishment task.

FIG. 17 is a conceptual diagram of replenishment in an exemplary RID.

FIG. 18 is a flowchart illustrating a replenishment task in an exemplaryRID.

FIG. 19 is a flowchart illustrating aspects of a replenishment task inan exemplary RID.

FIG. 20a is a conceptual diagram illustrating an exemplary RIDtransferring filled bins from an ISU to an operator station as part of apurge task.

FIG. 20b is a conceptual diagram illustrating an exemplary RIDtransferring empty bins from an operator station to an ISU as part of apurge task.

FIG. 21a is a flowchart illustrating replenishment in an exemplary RIDusing an OAD.

FIG. 21b is a flowchart illustrating purge in an exemplary RID using anOAD.

FIG. 22a illustrates a side view of a drawer in an exemplary ISU, beforebin compression by a robot.

FIG. 22b illustrates a side view of a drawer in an exemplary ISU, afterbin compression by a robot.

FIG. 23a is a top view of a pin-mounted bin.

FIG. 23b is a front view of a pin-mounted bin.

FIG. 23c is a top view of a rack for pin-mounted bins.

FIG. 24a is the first view in a sequence illustrating rack compressionor squeezing with pin-mounted bins.

FIG. 24b is the second view in a sequence illustrating rack compressionor squeezing with pin-mounted bins.

FIG. 24c is the third view in a sequence illustrating rack compressionor squeezing with pin-mounted bins.

FIG. 24d is the fourth view in a sequence illustrating rack compressionor squeezing with pin-mounted bins.

FIG. 24e is the fifth view in a sequence illustrating rack compressionor squeezing with pin-mounted bins.

FIG. 25 is a flowchart illustrating a purge task in an exemplary RID.

FIG. 26 is a flowchart illustrating multi-pick fulfillment in anexemplary RID.

FIG. 27 is a block diagram illustrating controller tasks to recover froma system interruption or failure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

This description provides embodiments of the invention intended asexemplary applications. The reader of ordinary skill in the art willrealize that the invention has broader scope than the particularexamples described here. It should be noted from the outset that thedrawings, and the elements depicted by the drawings, are not necessarilyto scale and may not show all details. Elements displayed in drawingsmay be confined to ones deemed relevant to the scope of illustrativeembodiments.

A robotic inventory dispensary (RID) 200 stores and dispenses productitems 245 to consumers 110. As summarized by FIG. 1, a user 100 of anRID 200 is a person who has access to an RID 200 under normaloperations. A user 100 might be a consumer 110, an operator 120, or aservice technician 140. An operator 120 might handle manual aspects ofproduct replenishment or purge. A service technician 140 might accessthe RID 200 for testing, upgrade, or repairs. We use the term “consumer”not in the economic sense, but rather as a consumer of the primaryfunction of an RID 200; namely, dispensing product items 245 on demand.A consumer 110 might be a staff member 112 or a customer 111. A consumer110 might also be another automated system 113. A staff member 112 mightbe, for example, a person who fulfills orders within a retail store or adistribution center (DC). A person might be a user 100 both as anoperator 120 and as a staff member 112. An RID 200 may dispense productitems 245 directly to customers 111 in a store. In some embodiments orimplementations, an operator 120 might also be a consumer 110.

FIG. 2 is a block diagram illustrating functional and structuralcomponents of an exemplary robotic inventory dispensary (RID) 200. AnISU 210 stores product items 245 under the management of a controller255. The ISU 210 of an RID 200 might have one or more modular units orhousings; one or more robots 205; access by one mechanism or severalmechanisms, or one or more locations. For example, an RID 200 mightdispense product items 245 to customers 111, but also dispense productitems 245 to staff members 112 using a different robot 205 and at adifferent location, possibly in a backroom of a store. The RID 200 mighthave dispensing chutes 220 at multiple locations; for example, a chute220 in front of an ISU 210 for customers and another behind the ISU 210for staff members 112. There may also be a chute 220 for dispensingproduct items 245 to an operator 120.

An operator 120 might manually add or remove product items 245 from anRID 200 through an operator access system at an operator station 270.Access by the operator 120 to product items 245 might be by a conveyor275, or by an operator access drawer (OAD) 280, or both. There may bemore than one OAD 280 to improve efficiency. During replenishment, forexample, the robot 205 might be removing already filled bins 230 fromone OAD 280 while the operator 120 fills bins 230 in another. Theconveyor 275 and the OAD 280 are examples of operator-access devices,which give an operator 120 access to bins 230 for manual tasks.

The controller 255, executing logic 260, manages equipment and maintainsdata necessary to carry out tasks of the RID 200. The data is saved in,and accessed from, a database system 265.

RIDs 200 can vary in prioritization of goals for their organization. Forexample, a given system might be prioritized to keep all product items245 of a given model in the same area of an ISU 210. Another systemmight seek primarily to minimize empty space in the ISU 210.prioritization schemes 975 that minimize the time to respond to arequest from a consumer 110, balancing replenishment/purge operationsand space utilization, will be discussed in connection with FIGS. 14aand 14 b.

The controller 255 of an RID 200 can preferably handle any and all ofthese prioritization schemes 975. To achieve this, a controller 255 willpreferably execute logic, and maintain data in the database system 265,to allow a single product item 245 to be stored in, and removed from,any given location within the ISU 210. In other words, the RID 200 is arandom-access storage system. The RID 200 may use a scanning system 215,including one or more scanners, to identify bins 230 and product items245.

Priorities for the RID 200 may evolve over time due to empiricalexperience or changing circumstances. Such new priorities might beimplemented by merely changing the prioritization scheme 975. An RID 200might have several built-in prioritization modules, and a givenprioritization module might have a changeable options or parameters thatconstrain how prioritization is done. An operator 120 might be able tochange a prioritization module or a prioritization parameter though theoperator UI 250. Because a priority module might be configured bychanging parameter values, or replaced with another prioritizationmodule, on operator command, the same ISU 210 can therefore be used formany different purposes and in many different contexts.

Preferably, a prioritization scheme will be selected so that productitems 245 of a given model will be removed on a first-in first-out(FIFO) basis. The FIFO approach seeks to achieve a relatively uniformISU 210 residence for a product model. Other schemes, such as last-infirst-out (LIFO), are also with scope of embodiments. For example, aprioritization scheme 975 might prioritize minimization of retrievaltime, without regard to shelf life. In this prioritization scheme 975, arobot 205 might simply grab (i.e., couple to and lift) the product item245 closest to the current position of its hand 386.

Within the ISU 210, product items 245 may be stored in bins 230,preferably one product item 245 per bin 230. The bins 230 may beorganized into drawers 240 in the ISU 210. A drawer 240 may be a framestructure, or it might have one or more solid sides. A drawer 240 mayopen into a tray 371, giving the robot 205 access to its contents. Ashelf 373 of the robot 205 will preferably include two such trays 371,left and right, but other numbers of trays 371 are possible. The trays371 are examples of temporary bin-holding receptacles. The ISU 210 mayinclude a section (e.g., a column 410) of empty bin storage 235 reservedfor empty bins 230. The controller 255 commands one or more robots 205as its agents to move bins 230 and product items 245 throughout the RID200 as needed to implement the tasks of the controller 255.

The robot 205 may move bins 230 to/from a conveyor 275. The conveyor 275may be used to transport bins 230 between an operator station 270, wherean operator 120 has access to bins 230 to assist in replenishment/purgeoperations regarding product items 245 in the RID 200. The operatorstation 270 may include an operator UI 250 whereby the operator 120 caninteract with the controller 255 by entering data and instructions, andby receiving information.

An RID 200 may have an OAD 280. An OAD 280 might be used forreplenishment and purge, initiated by an operator 120, or for dispensingof product items 245 to a staff member 112. A given RID 200 might havezero or more conveyors 275 and zero or more OADs 280, in anycombination. Preferably, when an OAD 280 is opened, it projects out froma side of the ISU 210, giving access to the operator 120 to insert bins230 or product items 245, and to remove bins 230 or product items 245.When the OAD 280 is closed, it behaves as a drawer 240 of the ISU 210,giving the robot 205 access to the OAD 280 and its contents.

The RID 200 may include a consumer UI 225 in a consumer station 226,whereby a consumer 110 may request a product item 245. A first consumerUI 225 might dispense product items 245 to customers 111; a secondconsumer UI 225, to staff members 112. A robot 205 may transfer theproduct item 245 to a chute 220 for dispensing it to a consumer 110. AnRID 200 may also include a chute 220 that dispenses product items 245into the operator station 270 for an operator 120.

In some embodiments, the consumer UI 225 might act as, in effect, asmart vending machine. The consumer UI 225 might include a Point-of-sale(POS) system 290, requiring payment before a product item 245 isdelivered to the consumer 110. Such a consumer UI 225 may accept variousforms of payment, such as cash, credit card, or smart phone accountscanning. Alternatively, the product items 245 might be first deliveredto the consumer 110 without up-front payment. The consumer 110 mightthen take the items to a separate POS station for payment and checkout.This approach might be appropriate where a store's inventory is splitbetween an RID 200 and more traditional retail display units, such asshelves, racks, and counters.

In the case of a DC, no payment may be required at the consumer UI 225.However, some form of identification might be required by the consumerUI 225 of a staff member 112 requesting product items 245, in order totrack product items 245 and to maintain accountability.

FIG. 3a is a front view of a robot 205 and an ISU 210 of an exemplaryRID 200. FIG. 3b is a Cartesian coordinate system 350 that is helpful indescribing an RID 200. FIG. 3a is viewed in the y direction. Thisparticular ISU 210 is arranged into a module that is a grid five drawers240 wide and seven drawers 240 high. The rightmost column 410 isreserved for empty bin storage 235, and is shown shaded. If productitems 245 are marked with optical-type identifiers (IDs), such as abarcode or 2D barcode, then bins 230 will preferably be transparent, ortranslucent, on all sides. Preferably the ISU 210 will have a rigidstructure and have essentially the shape of a rectangular solid.

A robot 205 accesses drawers 240 in the ISU 210, and bins 230 within thedrawers 240. The illustrated robot 205 has an articulated arm 380. Inthe illustrated embodiment, the arm 380 can swivel, tilt, and bend; ahand of the arm can couple to, lift, and move bins 230. The robot 205has a shelf 373 onto which it can slide out up to two drawers 240 intotrays 371 on either side of the arm 380 in order to insert, remove,rearrange, or compress bins 230 within a drawer 240. The shelf 373 canmove vertically along one or more posts 370 as indicated by arrows 330;the robot 205 illustrated in FIG. 3a has two posts 370. The posts 370move left/right along one or more tracks 372, as indicated by arrows320; the robot 205 illustrated in FIG. 3a has a track 372 at the top andanother at the bottom, but other arrangements for horizontal movementare possible.

FIG. 3c is a breakout from FIG. 3a that shows more detail of anexemplary arm 380. This arm 380 has a base 381 that can swivel asindicated by arrow 395. The arm 380 may have a top segment 384 fromwhich a grabber or hand 386 is suspended; in this case, by segment 385.The hand 386 can grab, lift, and translate bins 230, and can open andclose drawers 240. The base 381 and top segment 384 of the arm 380 areconnected by segment 382 and segment 383. These segments can tiltrelative to each other and also relative to base 381 and segment 384, asindicated by arrows 390 a, 390 b, and 390 c. Thus, arm 380 can swivel,bend, and tilt to give the hand 386, which can itself rotate asindicated by arrow 396, a wide range of positions and orientations. Thearm 380 might also have an extensible or telescopic segment (notshown)—e.g., in base 381—that allows it to move vertically. In FIG. 3a ,the arm 380 moves vertically along with shelf 373. Of course, otherconfigurations of a robot 205 and, in particular, of an arm 380, canprovide similar functionality and are within the inventive scope. Insuch other embodiments, the robot 205 can still be capable of randomaccess to individual bins 230 containing product items 245.

FIG. 3d is a stick diagram showing an alternative arrangement of tiltaxes 390 a, 390 b, and 390 c for a hand 386 a of a robot 205.

The horizontal and vertical motion of the shelf 373 and arm 380 may behandled by a robot that is separate from the robot 205 that opensdrawers 240 and moves bins 230. However, both robots 205 are undercommon control of a controller 255, and so may be considered a singlerobot or robotic system.

FIG. 4 is a conceptual diagram illustrating an exemplary storagehierarchy in an ISU 210. The ISU 210 is organized into vertical columns410. The drawers 240 are supported by racks 400 arranged in the columns410, as shown in more detail in FIGS. 12a, 12b, 13a, and 13b . Thedrawers 240 may be extended onto the shelf 373—e.g., into trays 371—togive the arm 380 access. Bearings or rollers (not shown) or othersimilar mechanism may facilitate such extension. The robot 205 may openand close drawers 240 by pulling or pushing handles on either side of adrawer 240, proximate to the end of the drawer 240. The bins 230 mayhang from two rails 500 of a drawer 240 by a lip structure, in a mannersimilar to well-known hanging file folders. Alternatively, the bins 230may have downward-extending pins that mate with holes in the rails 500,thereby ensuring proper alignment. The robot 205 may use the pins 2320to lift a bin 230, possibly by magnetic attraction between the hand 386and the pins 2320. The bins 230 may have variable depths and/or heights.A bin 230 may be empty, or may hold a product item 245.

FIG. 5a is an isometric view of an exemplary RID 200 using a conveyor275 for operator access. In addition to examples of many of thecomponents of an RID 200 already described, the figure shows rails 500upon which bins 230 rest in the ISU 210. FIG. 5b is an isometric view ofan exemplary RID 200 having an OAD 280 instead of a conveyor 275 foroperator 120 access. In the embodiment shown, the operator 120 hasaccess to the contents (i.e., bins 230, either empty or containingproduct items 245) when the OAD 280 is open; when the OAD 280 is pushedclosed, the OAD 280 behaves like other drawers 240 in the ISU 210 towhich the robot 205 has access.

FIG. 6 is a block diagram illustrating exemplary tasks 600, some or allof which that might be executed by a robot 205 in an RID 200. Theseinclude: open and close 605 the drawers 240; insert 610 a bin 230 intoan open drawer 240; remove 615 a bin 230 from an open drawer 240; insert620 a bin 230 into a temporary location, such as empty bin storage 235;remove 625 a bin 230 from a temporary location; transfer 630 a bin 230from a drawer 240 to a conveyor 275 or to an OAD 280; transfer 635 a bin230 from a conveyor 275 or an OAD 280 to a drawer 240; insert 645 aproduct item 245 into a bin 230; remove 650 a product item 245 from abin 230; dump 655 a product item 245 into a chute 220 to be dispensed toa consumer 110; scan 660 an identifier of a bin 230; scan 665 anidentifier (e.g., a UPC) of a product item 245; compress 670 the bins230 in a drawer 240; translate 675 the arm 380 laterally; translate 680the arm 380 vertically; and sensibly indicate 685 success of anoperation. As an example of this last task, an audio signal, a visualsignal on a UI, or even an action by the robot 205 (e.g., a victorydance) might be used to indicate that an operation, such as dispensingseveral product items 245 to a consumer 110, is complete.

FIG. 7 is a block diagram illustrating exemplary functional andstructural components of a controller 255 of an RID 200. Note that thecontroller 255 may be located in the robot 205, elsewhere in the RID200, or might remotely and access the RID 200 over a communicationsystem 720 through a network connection. The functionality may bedivided among systems and locations. The controller 255 includes aprocessing system 710 that includes at least one processor, and storage730 that includes computer-accessible tangible storage. An operator 120might interact with controller 255 through an operator UI 250.

FIG. 8 is a block diagram illustrating exemplary controller tasks 800that might be executed by a controller 255 of an RID 200. These include:direct 810 activities of a robot 205; handle 820 single- and multi-picktransfers of product items 245; control 830 a conveyor 275; control 835an OAD 280; interact 840 with an operator 120 through an operator UI250; execute 850 requests from an operator 120; maintain 855 inventoryof bins 230 locations, depths, and heights; manage 857 replenishment;manage 860 inventory of product item 245 locations in bins 230; maintain870 inventory of drawer 240 contents an layouts; manage 880 a table ofdrawer 240 heights; interact 885 through a consumer UI 225; fulfill 890requests or orders from a consumer 110; manage 895 billing and payment;manage 897 purge; and handle 898 failure prevention and recovery.

FIG. 9 is a block diagram illustrating exemplary types of data in adatabase system 265 that might be maintained and managed by a controller255 of an RID 200 in storage 730. Such data types include: ISU 210 gridlayout 905; for each bin: id, drawer, position in drawer, height, depth,product contents 910; robot control commands 920; product model data930, such as categories (e.g., digital camera), bin locations; dataabout consumers 932; system state data 934; product item data 934;drawer data 940—for each drawer: height, depth, bins, positions of bins;data about column and rack positions and content 950; for each categoryof product: product model 960; logic to perform controller functions970; task prioritization schemes prioritization schemes 975; and dataregarding transactions with customers 980.

FIGS. 10a and 10b are left side and front views, respectively, of a bin230 containing a product item 245. The front view is a cross section atA-A through the side view. The front view shows that the bin 230 restsby means of two hangers 1050, which each straddle a respective rail 500on either side of the bin 230. The rails 500 are part of a column 410 inthe ISU 210.

Preferably the bin 230 will be transparent or translucent, so theproduct items 245 in the ISU 210 can be seen by consumers 110, by anoperator 120, and by technicians for testing, upgrade, maintenance, andrepair. In other embodiments, the bins 230 may be opaque. As mentionedpreviously, the means for identifying bins 230 may influence the choicebetween transparent and opaque bins 230.

We will call the z-dimension of a bin 230 its height; the y-dimensionits depth; and the x-dimension its width. So FIG. 10a shows the heightand depth of the bin 230; FIG. 10b shows its height and width.

The exemplary hangers 1050 shown in FIG. 10a might extend the full depthof the bin 230, but hangers 1050 might only extend a portion of thatdimension, and may have two or more subcomponents. See, for example,FIG. 17, where the hangers 1050 are more similar to those of hangingfile folders.

FIGS. 11a and 11b show another bin 230 hanging on two rails 500. Thefront view is a cross section at B-B through the side view. Comparisonof these figures with the previous two illustrates that bins 230 mightdiffer in height or depth, accommodating a broad product assortment,while reducing the amount of unused space within the ISU 210 relative toa system that uses equal height or equal depth bins 230 for all productitems 245.

FIG. 12a is a front cross-sectional view through a column 410 of rails500 and bins 230 in an exemplary ISU 210; the rails 500 are positionedto form drawers 240 that are variably-spaced in the vertical, asindicated by distances 410 a-410 e. Bins 230 a, 230 b, and 230 c areeach of different heights; and bins 230 a and 230 b contain productitems 245 of different heights, namely product items 245 a and 245 b.

FIG. 12b is comparable, but for equally-spaced rails 500 and drawers240. The drawers 240 are separated vertically by a distance 420, say D.Fixed height bins, such as 230 d and 230 e, can hold product items 245of different heights, such as product items 245 c and 245 d; overall,however, variable vertical spacing is preferable because it can reducewasted space when the ISU 210 stores a variety of types of product items245.

FIG. 13a illustrates how equally-spaced mount points 1340 (indicated byarrows) for variably-spaced racks 400 might be used to implementvariably-spaced rails 500 in an exemplary ISU. Each rail 500 attaches toa post 1330 at a mount point 1340. The rails 500 and posts 1330 form acolumn 410 of drawers 240 for hanging bins 230 in the ISU 210. A finespacing of the available mount points 1340 relative to the height of thesmallest bin 230 provides flexibility in the height of drawers 240. Thevertical positions of the rails 500 may be controlled and setautomatically by the controller 255, possibly in response to a directivefrom an operator 120. In this case, the rails 500 may move vertically ontracks. Alternatively, in some embodiments, changes to positions of therails 500 might require manual positioning.

FIG. 13b illustrates how equally-spaced rails 500 might be used tofacilitate bins 230 of varying height. Bins 230 d and 230 f are eachtaller than the fixed distance between rails 500, and overlap rails 500a and 500 b, respectively. Bin 230 e has a smaller height and fitsbetween two vertically-adjacent rails 500. Switching between railconfigurations might be initiated by an operator 120 through an operatorUI 250. For example, an operator 120 might specify that all drawers 240in column A will have height X, while those in column B will have height2X. With the approach of FIG. 13b , bin height changes can be made byautomatically by the system, or by an operator 120, without changingpositions of rails 500. This approach is preferable to that of FIG. 13ain embodiments in which rails 500 of the ISU 210 would have to berepositioned manually.

Within a given region of the ISU 210 (e.g., within a column 410), themaximum height of a bin 230 might be set to be less than mD for someinteger m greater than 1. In this area, some of the bins 230 mayvertically overlap, or extend below, rails 500. This integer might bechosen for the region by logic of the controller 255 to conserve spacein the RID, or it might set manually by an operator 120 through anoperator UI 250.

FIG. 14a is a flowchart illustrating how exemplary logic 260 in an RID200, typically executed by a controller 255, might prioritize tasks offulfilling purchase requests; replenishment/purge; and compression ofdrawers 240. The depicted process might continue indefinitely over anentire period when the RID 200 is operational. After the start 1400, thelogic 260 checks whether 1410 there is a consumer 110 request pending.Preferably, fulfillment of consumer 110 requests will have the highestpriority in the system. If so, the robot 205 may grab 1450 theappropriate bins 230 and dispense the product items 245 to the consumer110. Otherwise, the logic 260 checks whether 1420 a replenish or purgerequest (or possibly some other request from the operator 120) ispending. If so, then the controller 255 services 1460 the request fromthe operator 120. Otherwise, in background, the robot 205 may squeeze1470 or compress bins 230 in drawers 240 when needed 1430 to reduce anywasted space in the ISU 210. Note that in some embodiments, the robot205 might perform compression at other times, such as when a new bin 230is added to a drawer 240, or an existing bin 230 is removed. Aftercompleting a task, flow returns to step 1410.

FIG. 14b is a state diagram illustrating an alternative priority systemfor an exemplary RID 200. The diagram shows five states, namely: idle1480; service 1481; customer request 1482; replenish load or purgeunload operator request 1483; and distribute, consolidate, or defragment1484. The RID 200 returns to idle 1480 after completing a task specifiedby any of the other states, as indicated by arrows 1490 a-1490 d.Ellipses representing states other than idle 1480 show with a boldfacenumeral how the corresponding tasks might be prioritized priority, with‘1’ being the highest priority. The load and unload requests from theoperator 120 are initiated at the operator UI 250—a load-priorityrequest when the operator 120 either needs empty bins 230 for newproduct items 245 or has completed filling some bins 230 with newproduct items 245; and an unload-priority request when the operator 120requests that the RID 200 remove all instances of a given product typeor requests that empty bins 230 be returned to the ISU 210. Thedistribute-, consolidate-, and defragment-priority tasks are done inbackground.

FIG. 15 is a conceptual diagram illustrating how an exemplary RID 200might fulfill a request from a consumer 110 for one or more productitems 245. As mentioned previously, the consumer 110 here might actuallybe a staff member 112 if, for example, the RID 200 picks product items245 for shipping from a DC. The consumer 110 makes the request through aconsumer UI 225, located in a consumer station 226. The robot 205removes the product items 245 from the ISU 210, as indicated by arrow1520 and, as indicated by arrow 1521, places them into a chute 220 orother dispensing means, thereby giving the consumer 110 access toproduct items 245. The RID 200 may also include an operator station 270,having an operator UI 250, and a conveyor 275 to move bins 230, whetherempty or containing a product item 245, between the ISU 210 and theoperator station 270, as indicated by arrow 1530.

FIG. 16a is a conceptual diagram illustrating an exemplary RID 200transferring empty bins 230 from an ISU 210 to an operator station 270as part of a replenishment task. The operator 120 may initiate ortrigger the task by a request through the operator UI 250. In response,the controller 255 accesses in storage 730 a database system 265 todetermine locations within the ISU 210 of a plurality of empty bins 230.In response to receiving a command from the controller 255, the robot205 transfers the empties to the conveyor 275 as indicated by 1605. Asindicated by 1606, the conveyor 275, in turn, moves the empty bins 230to the operator station 270, where a number of new product items 245await.

FIG. 16b is a conceptual diagram illustrating an exemplary RID 200transferring filled bins 230 from an operator station 270 to an ISU 210as part of a replenishment task. The operator 120 fills the bins 230with the product items 245, as indicated by arrow 1610. When finishedfilling, operator 120 might request through the operator UI 250 that theRID 200 continue the replenishment task. Upon receiving the request, thecontroller 255 causes the robot 205 to (1) move the bins 230 to beaccessible to the robot 205—in the figure, this is by a conveyor 275, asindicated by arrow 1615, but it could be done alternatively by closingan OAD 280; (2) grab each bin 230 from the conveyor 275; and (3)transfer the filled bins 230 into the ISU 210, as indicated by arrow1620. The location selected by the controller 255 might be chosenaccording to a prioritization scheme 975. A bin 230 might be initiallyplaced into a temporary storage location, and later transferred by therobot 205 to another location that is chosen according to theprioritization scheme 975; this later transfer might be done in abackground mode in order to avoid impacting higher priority tasks.

FIG. 17 is a conceptual diagram illustrating bins 230 being filled by anoperator 120 with product items 245, and placed on rails 1700 of aconveyor 275. As indicated by arrow 1710, conveyor 275 moves the filledbins 230 to where they can be accessed by robot 205.

FIG. 18 is a flowchart illustrating a replenishment task in an exemplaryRID 200. After the start 1800, a signal to replenish is received 1810through the operator UI 250. Replenishment might not start immediatelyif delayed according to system priorities. See, e.g., FIGS. 14a and 14b. Once replenishment has priority 1820, the robot 205 transfers 1830empty bins 230 from empty bin storage 235 to conveyor 275, which thenmoves 1840 the bins 230 to operator station 270. The operator 120 fills1850 the empty bins 230 with product items 245, and places the filledbins 230 onto the conveyor 275. Through the operator UI 250, operator120 signals 1860 that the system continue with replenishment. Theconveyor 275 moves 1870 the filled bins to be accessible by robot 205.The robot 205 scans 1880 the bins 230 and the product items 245 using ascanning system 215 to obtain their IDs. The robot 205 may lift the bin230, and using its attenuation features, tilt or rotate the bin 230 inorder to perform the scan of a UPC or other identifier on the productitem 245. The controller 255 records the incoming product items 245 instorage 730. The process ends 1899.

A scanning system 215 may be mounted on the robot 205 or on the ISU 210.More than one scanning system 215 might be used to improve scanningspeed by reducing the time required for the robot 205 to find theproduct item identifier, or to divide tasks. For example, one scannermight scan a bin identifier, and the other scanner might scan a productitem identifier. If the product item identifier is a UPC or a 2Dbarcode, then the bins 230 should be mostly or wholly transparent ortranslucent. If the product identifier is a radio-frequencyidentification (RFID) chip, or other smart identifier, then opaque bins230 will permit scanning. In any case, a scanning system 215 will bedirectly or indirectly under control of the controller 255.

FIG. 19 is a flowchart illustrating how step 1880 of FIG. 18 might bedone. After the start 1900, the robot 205 selects and opens 1910 adrawer. The robot 205 grabs 1920 a bin 230 containing a product item 245from either a conveyor 275, from an OAD 280, or from temporary storage,depending upon embodiment. The robot 205 scans 1925 the bin 230 toidentify it. The robot 205 scans 1930 the product item 245 to obtain itsproduct item identifier, and places the bin 230 into a drawer 240. Thecontroller 255 updates 1935 the inventory data in the database system265; in particular, the controller 255 associates the bin 230, theproduct item 245, and the particular location with the drawer 240. If1940 there are more bins 230 ready to be placed into this drawer 240,then the process repeats from step 1920. Otherwise, the robot 205 closes1950 the drawer 240. If 1960 there are more bins 230 to move to the ISU210, then the process returns to step 1910. Otherwise, the process ends1999.

FIG. 20a is a conceptual diagram illustrating an exemplary RID 200, inan embodiment with a conveyor 275, transferring filled bins from an ISU210 to an operator station 270 as part of a purge task. The robot 205moves bins 230 containing product items 245 to the conveyor 275, asindicated by arrow 2000. The conveyor 275 moves the bins 230 to theoperator station 270, as indicated by arrow 2010. In FIG. 20b , theoperator 120 removes the product items 245 from the bins 230, asindicated by arrow 2020. The empty bins 230 are carried by the conveyor275, as indicated by arrow 2030. The robot 205 removes the empty bins230 and returns them to the ISU 210, as indicated by arrow 2040,preferably to empty bin storage 235.

Note that FIG. 15-20 b will apply, essentially unchanged, if theconveyor 275 is replaced with an OAD 280. This is illustrated by thefollowing two figures, where we explicitly describe embodiments using anOAD 280 rather than a conveyor 275.

FIG. 21a is a flowchart illustrating replenishment in an exemplary RID200 using an OAD 280. After the start 2100, an operator 120 initiates2110 replenishment through the operator UI 250 with a command or signalto the controller 255. The system moves 2120 some empty bins 230 to anOAD 280. After filling empty bins 230 with product items 245, theoperator 120 commands or signals 2130 through the operator UI 250 thatthe operator 120 portion of the replenishment task is complete. The RID200 moves 2140 the empty bins 230 to a temporary location in the ISU210. The RID 200 reorganizes 2150 the bins 230 into more permanentlocations in the ISU 210, compressing drawers 240, either immediately orin background.

FIG. 21b is a flowchart illustrating purge in an exemplary RID 200 usingan OAD 280. After the start 2160, an operator 120 initiates 2170 thepurge operation through the operator UI 250, identifying one or moreproduct items 245 or product types (see the Background section) to bepurged. The RID 200 moves 2180 the affected bins 230 to the OAD 280. Theoperator 120 removes the product items 245 from the bins 230, andsignals 2185 through the operator UI 250 that the operator 120 portionof the purge task is complete. The RID 200 moves 2190 the empty bins 230to empty bin storage 235. The process ends 2199.

Compression might be done by the RID 200 on a bin-by-bin basis as bins230 are added or removed. In some embodiments, however, compressionmight be done in whole or in part as a separate task, preferably in abackground mode, without interfering with more important system taskssuch as requests from a consumer 110 or an operator 120. FIGS. 22a and22b , respectively, illustrate a side view of a drawer 240, before andafter compression or squeezing by a robot 205. The direction ofcompression is indicated by arrow 2200.

An RID 200 might hang bins 230 in drawers 240 in various ways. Forexample, the bins 230 in FIGS. 10a, 10b , and 17 are suspended fromhangers. We will refer to the portion of a bin 230 that overhangs a rail500, from which the bin 230 is suspended, as a tab 2325. The bins 230 inFIG. 23a-24e hang instead secured by pins 2320 through the tabs 2325.The bins 230 shown are secured by a pair of pins 2320, one per side.Other embodiments might use two or more pins 2320 per side. FIGS. 23aand 23b are top and front views, respectively, of a pin-mounted bin2300. The pins 2320 may be made of metal or other hard substance(s),such as a glass or a plastic. The walls of the bins 230 may be made ofplastic, glass, acrylic, metal, or other rigid substance(s). FIG. 23ashows the interior wall 2310 of a bin 2300.

FIG. 23c is a top view of a rack 2340, a rack 400 to support one side ofa bin 2300, which includes pin holes 2330 for the pins 2320. The pinholes 2330 are preferably spaced by a distance less than or equal to thedepth of the narrowest bins 230. Those bins 230 with greater depths mayoverlap one or more pin holes 2330.

FIG. 24a-24e is a sequence of figures that illustrate an embodiment ofcompression by a platform 2410 of a drawer 240 of a bin 2300. Prior tothe start of the sequence, the robot 205 has opened the drawer 240 bypulling on grip 2400. FIG. 24a shows four bins 2300, taken from theperspective of section A-A of FIG. 23c . Between FIGS. 24a and 24b , abin 2300 has been removed by the robot 205.

A platform 2410 moves underneath the third and fourth bins 2300. Theword “platform” does not necessarily imply a solid structure; platform2410 might be a frame. A platform 2410 might be a component of a drawer240 of the ISU 210, or a platform 2410 might be part of a tray 371 or ashelf 373.

In FIG. 24c the platform 2410 has lifted, as indicated by arrow 2420,two of the bins 2300, thereby disengaging their pins 2320 from thecorresponding pin holes 2330 of rack 2340. In FIG. 24c , as indicated byarrow 2430, platform 2410 has moved the two bins 2300 left, so thattheir pins 2320 align with pin holes 2330 in the rack 2340. In FIG. 24e, as indicated by arrow 2440, the platform 2410 lowers to set the twobins 2300 into their compressed new location.

FIG. 25 is a flowchart illustrating a purge task in an exemplary RID200, using a conveyor 275. After the start 2500, the operator 120 enters2510 a request to purge a product type through an operator UI 250. When2520 the purge task has become the system's top priority and 2530 thereare bins 230 yet to be purged, then, after opening a drawer 240, therobot 205 transfers 2540 one or more bins 230 from the drawer 240 to theshelf 373. In this embodiment, the robot 205 immediately compresses 2550the drawer 240. If no more bins 230 remain to be purged, then the robot205 moves 2560 the affected bins 230 from the shelf 373 to the conveyor275. Alternatively, the robot 205 might move each bin 230, immediatelyafter the bin 230 is located, from the shelf 373, or from the drawer 240directly, to the conveyor 275. The controller 255 removes 2570 affectedproduct items 245 from the database system 265. The conveyor 275transports the bins 230 to the operator 120, who removes 2580 theproduct items 245 from the bins 230. The conveyor 275 transports 2590the empty bins 230 back to the robot 205, which 2595 stores the emptybins 230 in empty bin storage 235. Here, as elsewhere, the controller255 keeps track of which bins 230 are empty, and where each bin 230 islocated. The process ends 2599.

FIG. 26 is a flowchart illustrating multi-pick fulfillment in anexemplary RID 200. In multi-pick fulfillment, the robot 205 grabs two ormore bins 230 containing product items 245, holding them all temporarilybefore transferring them to the chute 220 or the conveyor 275. After thestart 2600, a request is received 2610 for a nonempty set of productitems 245, which might in some instances include two or more productitems 245. The request might originate from an operator 120, a consumer110, or other user 100. The next product item 245 becomes 2620 thecurrent product item 245. The robot 205 fetches 2630 the bin 230 holdingthe current product item 245. The robot 205 places 2640 the current bin230 onto the shelf 373. If 2650 there are more product items 245 in theset, the robot 205 transfers 2660 all the accumulated bins 230containing to the conveyor 275 or, depending on the request, theirproduct item 245 contents to the chute 220. Any empty bins 230 aretransferred 2670 by the robot 205 to empty bin storage 235. The processends 2699.

FIG. 27 is a block diagram illustrating controller 255 tasks 2700 torecover from a system interruption or failure. These include: save thesystem state 2710; restore the system state to where it was beforefailure 2720; check component state and repair any components ifnecessary 2730; save the state of any transactions, such as customerrequests or purchases 2740; restore the state of transactions to thestatus before failure 2750; complete a transaction that has beenpartially completed, such as partially fulfilled 2760; and mitigate anypartially completed transactions that cannot be fulfilled 2770 by, forexample, a refund or a credit to a credit or debit card.

Of course, many variations of the above method are possible within thescope of the invention. The present invention is, therefore, not limitedto all the above details, as modifications and variations may be madewithout departing from the intent or scope of the invention.Consequently, the invention should be limited only by the followingclaims and equivalent constructions.

1-15. (canceled)
 16. A robotic inventory dispensary, comprising: astorage unit to store a plurality of storage bins for respective productitems; and robotics to operate on the storage unit, the robotics undercontrol of a computerized controller, wherein the robotics is configuredto randomly access locations in the storage unit for placement andretrieval of the plurality of storage bins; wherein the robotics isoperable to retrieve multiple selected storage bins with a multi-pickselection operation, the multiple selected storage bins including two ormore storage bins respectively holding product items, and wherein themultiple selected storage bins are selected to satisfy a request forspecified items with the multi-pick selection operation.
 17. The roboticinventory dispensary of claim 16, the robotics including: a bin-holdingunit, the bin-holding unit including a shelf that moves with therobotics, wherein in response to the multi-pick selection operationhaving placed the multiple selected storage bins for all product itemson the shelf that are selected to satisfy the request for the specifieditems, the robotics transfers the product items from the multipleselected storage bins to a dispensing location.
 18. The roboticinventory dispensary of claim 16, the robotic inventory dispensarycomprising: a set of drawers in the storage unit, the set of drawersincluding a first drawer hosting a first storage bin containing a firstproduct item and a second storage bin containing a second product item,and a second drawer hosting a third storage bin containing a thirdproduct item; and a dispensing chute to receive selected product itemsretrieved by the robotics; wherein the robotics operates to place thefirst product item and the third product item in the dispensing chute,in response to retrieval of both of the first product item front thefirst drawer and the third product item from the second drawer.
 19. Therobotic inventory dispensary of claim 16, the robotics including: an armthat is articulated, so that the arm can tilt and swivel; a hand on thearm that can couple to, lift, and translate storage bins in the storageunit and can open drawers of the storage unit; and a bin-holding unitthat moves with the arm, the bin-holding unit adapted to hold themultiple selected storage bins during the multi-pick selectionoperation.
 20. The robotic inventory dispensary of claim 19, whereinusing the hand, the robotics further: couples to a first drawer of thestorage unit, opens the first drawer, couples to a first storage binheld by the first drawer, lifts the first storage bin, and places thefirst storage bin onto the bin-holding unit; while the first storage binis on the bin-holding unit and the first drawer is open, couples to asecond storage bin held by the first drawer, lifts the second storagebin, and places the second storage bin onto the bin-holding unit;couples to the first storage bin, and transfers a first product itemfrom the first storage bin into a dispensing chute; and couples to thesecond storage bin, and transfers a second product item from the secondstorage bin into the dispensing chute.
 21. The robotic inventorydispensary of claim 20, wherein using the hand, the robotics further:closes the first drawer; moves horizontally or vertically to a seconddrawer; while the first and second storage bins are on the bin-holdingunit, couples to the second drawer, opens the second drawer, couples toa third storage bin, lifts the third storage bin, and places the thirdstorage bin onto the bin-holding unit, and couples to the third storagebin and transfers a third product item from the third storage bin intothe dispensing chute.
 22. The robotic inventory dispensary of claim 16,wherein the request for specified items indicates multiple product itemsto retrieve of: a particular model, a particular functionality, or aparticular manufacturer or vendor.
 23. A system, comprising: a storageunit to store a plurality of storage bins for respective product items;robotics to operate on the storage unit; a controller operably coupledto the robotics, the controller to operate the robotics to retrievemultiple selected storage bins with a multi-pick selection operation,the multiple selected storage bins including two or more storage binsrespectively holding product items, and the multiple selected storagebins selected during the multi-pick selection operation to satisfy arequest specifying the respective product items; and a bin-holding unitaccessible by the robotics, the bin-holding unit to hold at least one ofthe multiple selected storage bins during the multi-pick selectionoperation.
 24. The system of claim 23, comprising: a computing device incommunication with the controller, the computing device including a userinterface to generate an electronic command that includes the requestand that the controller receives to retrieve the respective productitems from the multiple selected storage bins, the respective productitems including a first product item and a second product item.
 25. Thesystem of claim 24, comprising: a dispensing apparatus, the dispensingapparatus including a space to receive the first product item and thesecond product item in response to the robotics transferring therespective product items from the bin-holding unit, wherein thebin-holding unit is a shelf.
 26. The system of claim 25, comprising: apoint of sale system in communication with the controller, the point ofsale system to receive payment for the first product item and the secondproduct item before the robotics is controlled to place the firstproduct item and the second product item into the dispensing apparatus.27. The system of claim 23, wherein the request indicates multipleproduct items to retrieve of: a particular model, a particularfunctionality, or a particular manufacturer or vendor.
 28. A method,performed with electronic operations in a processing system of a roboticinventory dispensary, the robotic inventory dispensary adapted to storeand retrieve a plurality of product items in a storage unit usingrobotics, and the electronic operations including: receiving, by acomputerized controller of the processing system, a request to retrievetwo or more requested product items of the plurality of product itemsstored in the storage unit, the request indicating a productspecification used to select the two or more requested product itemsfrom among the plurality of product items; determining, by thecomputerized controller using a database system, a set of unique storagebins corresponding to the respective product items of the two or morerequested product items, and respective locations of the set of uniquestorage bins in the storage unit; operating the robotics in response toa command from the computerized controller, to retrieve respectivestorage bins for each item of the two or more requested product itemsand transfer at least a first storage bin holding a first product itemof the two or more requested product items onto a holding area; andoperating the robotics to remove the first storage bin from the holdingarea and place the first product item of the first storage bin into adispensing apparatus, in response to retrieval of all of the respectivestorage bins from the storage unit for each item of the two or morerequested product items.
 29. The method of claim 28, wherein operationsperformed by the robotics to retrieve a respective storage bin includeopening, by an arm of the robotics, a first drawer of the storage unitto be proximate to a tray that moves with the arm, the tray providingthe holding area, and wherein operations performed by the robotics totransfer the respective storage bin onto the holding area includecoupling to and lifting the respective storage bin by a hand attached tothe arm, onto the tray.
 30. The method of claim 28, wherein thedispensing apparatus is an operator access drawer, the operator accessdrawer adapted to receive a plurality of storage bins.
 31. The method ofclaim 28, wherein the dispensing apparatus is a conveyor that transportsa plurality of storage bins between the storage unit and an operatoraccess area.
 32. The method of claim 28, wherein the dispensingapparatus is a dispensing chute.
 33. The method of claim 28, wherein theproduct specification indicates multiple product items to retrieve of: aparticular model, a particular functionality, or a particularmanufacturer or vendor.
 34. The method of claim 28, wherein the requestto retrieve the two or more requested product items is generated througha user interface of a computing device operated by a customer.
 35. Themethod of claim 28, the electronic operations further including:receiving, through a point-of-sale payment system, an indication ofpayment for the two or more requested product items, the indication ofpayment received before the robotics places any of the two or morerequested product items into the dispensing apparatus.
 36. The method ofclaim 28, wherein the holding area is provided by a bin-holding unit,and wherein to retrieve and transfer respective storage bins for the twoor more requested product items with the robotics, operations areperformed including: translating a base section of an arm of therobotics horizontally in a plane parallel to a face of the storage unit;translating the bin-holding unit, which is attached to the base section,horizontally together with the base section; translating the basesection vertically in the plane; and translating the bin-holding unit,vertically together with the base section, causing the bin-holding unitto receive the respective storage bins on the bin-holding unit.